S. Schwarzengrund¶

At a Glance


Antigenic Formula	`1,4,12,27:d:1,7`
Serogroup	O:4 (B)
NCBI Pathogen Detection	View isolates

Background Information¶

Salmonella enterica subsp. enterica serovar Schwarzengrund (antigenic formula 1,4,12,27:d:1,7) is a serovar of the O:4 (B) serogroup. S. Schwarzengrund is among the most common serovars in non-clinical non-human sources in the US. This serovar was first reported in North America in 1952 when it was isolated from turkey poults. A case report from Japan indicates that pyogenic sacroiliitis, a rare type of extraintestinal infection, has been reported for this serovar.

Genetic Characteristics¶

Serovar Schwarzengrund has been found to be polyphyletic with four lineages identified and one stand-alone singleton that does not cluster with any other Salmonella Schwarzengrund isolates. A study of antimicrobial resistance in global Salmonella isolates found that serovar Schwarzengrund was positively correlated with fluoroquinolone resistance. In addition, fluoroquinolone resistant strains have been linked to imported food in the US. Multidrug resistant (MDR) strains (e.g., resistant to dihydrostreptomycin, kanamycin, oxytetracycline, bicozamycin, trimethoprim, and sulfadimethoxine) have been linked to broilers in Japan. MDR S. Schwarzengrund was found to be transmitted from chickens to people in some countries in Asia. A serovar Schwarzengrund isolate was found to carry some markers of the plasmid to Emergent Salmonella Infantis (pESI).

Animal Reservoir¶

Poultry is the main reservoir of S. Schwarzengrund. This serovar has also been found in dogs.

Geographical Distribution¶

S. Schwarzengrund is widely distributed. This serovar has been reported to be prevalent in Asia and it has been found in Europe and the US as well.

Human/Animal Outbreaks¶

Outbreaks associated with S. Schwarzengrund have been reported in the US; in addition, in Denmark cases have been linked to Thai food products.

Year	Location	Associated source	Number of cases
2022	Europe: multi-country	Black pepper suspected	Not reported
2019	US - multistate	Ground turkey	7
2018	China	Spiced donkey meat	4
2007	US - Massachusetts	Exposure to poultry from live bird-market	62
2007	US - multistate	Dry pet food	79
1996-2000	US - Oregon	Person-to-person	11

Border Rejections¶

Year	Exporting country	Importing country	Associated source	Product category
2025	Hungary	Finland	Turkey meal	Feed materials
2021	Brazil	Germany	Black pepper¹	Herbs and spices
2020	Brazil	Germany	Black pepper²	Herbs and spices

¹Serovars Poona and Matadi were also found in this product

²Serovar Javiana was also found in this product

Recalls¶

Year	Location	Recalled food	Type
2019	US: Multistate	Turkey products	Poultry and poultry products